Tire pressure indicator



y 1951 R. STEVEN 2,552,068

TIRE PRESSURE INDICATOR 1 Filed Nov. 25, 1946 INVENTOR. @AY L. JrEL E/v.

Eatented May 8, 195i UNITED STATES PATENT OFFICE TIRE PRESSURE INDICATOR Ray L. Steven, Los Angeles, Calif.

Application November 25, 1946, Serial No. 712,186

3 Claims. 1

This invention relates to motor vehicles and more especially to a tire pressure indicator for registering the pressure of the respective tires at all times.

An object of the invention is to provide a simple, practical and inexpensive tire pressure indicator for motor vehicle tires.

Another object of the invention is to provide tire pressure indicating means whereby the pressure of the respective tires of a motor vehicle can be registered or indicated at the dash of the vehicle at all times, including the time the motor vehicle is being operated.

A further object of the invention is to provide improvements in a tire pressure indicator moorporating novel means for transmitting the indicated pressures through the axles of the vehicle to the dash.

An additional object of the invention is to provide a tire pressure indicator having a fixed pressure responsive element and a rotatable responsive element and novel thrust bearing means therebetween having improved means for lubrication of the bearing means.

Other objects and advantages will appear and be brought out more fully in the following specification considered with reference to the accompanying drawings throughout which like parts are designated by like numerals.

In the drawings:

Figure 1 is an elevation view partly in section showing a motor vehicle wheel and a tire pressure indicator of my invention associated therewith.

Figure 2 is an enlarged view in section showing the pressure responsive features also shown in Figure 1.

Figure 3 is a side elevation view of the structure shown in Figure 2.

Figure 4 is a view similar to Figure 2 showing a modified form of my invention.

Referring more particularly to the drawings I show a wheel 40, such as the wheel of a motor vehicle, having a suitable bearing mounting on an axle II, which is indicated as one of the fixed front axles of the vehicle, wheel Ill having a pneumatic tire I2 mounted thereon.

The tire pressure indicator of my invention comprises a casing l3 having a circular wall M, a circular wall consisting of an annular member l5 and a similar member I5a, and a cylindrical wall I6 suitably secured together as by screws or the like, as shown. Wall l5a is suitably secured as by pressed fit on a portion of axle I l and wall M has a central opening I! through which ex- 2 tends a reduced threaded end portion I8 of the axle.

Walls l5 and 15a are separated by an annular space or slot [5b for a purpose to be presently described. Casing i3 is secured on the axle by a clamping action of a nut I 9 on threaded end portion 58 which clamps wall E4 to a shouldered portion of the axle.

Casing it provides a housing for a shell which is rotatable therein, thrust bearings 2| being provided between the shell and wall [5, a bearing race 22 being provided to support the shell on axle H. Shell 2!) has a flange portion 23 and a pressure responsive element 24 is positioned in the shell, as shown. Element 24 may be of any desired type but is shown as being an annular inflatable bag having flexibility and expansibility in an axial direction and having a stem 25 which extends through slot [511 and is connected by tube or conduit 26 to tire I2 is such manner that the pressure in element 24 is that of tire l2 and fluctuates with it to expand element 24 on an increase of pressure and contract it upon a reduction of the tire pressure.

A plurality of pins 2'5 extend axially from shell 2!} through slot i511 and engage corresponding bores in the hub of wheel is in such manner that the shell 28 rotates with the wheel.

A fixed pressure responsive element 28 is contained in casing i3ladjacent wall It and has a stem 29 which extends through wall l4 and is connected by conduit 36 to a bore or passage 3! formed in the axle H, the inner end of bore 3i being connected to a conduit 32 which leads to a pressure indicating gauge 33 mounted on the dash of the motor vehicle.

An annular plate 3 is disposed in casing 13 adjacent pressure responsive element 28 and has an annular flange portion 33, the peripheral portion of the flange being guided axially in a recess 35 in cylindrical wall iii. A plate 31 is provided adjacent pressure responsive element 24 and is bearing mounted at 38 on axle ll and has a thrust bearing engagement 39 with flange 36 of plate 3 3. A plurality of thrust roller bearing members "is are suitably disposed as by a ring or cage ll between plates 3% and iii, it being apparent that plates 6% and 3? are slidable axially upon changes in pressure in pressure responsive element 2Q, plate as bearing against pressure responsive element 28 so that the pressure in element 26 is reflected as the pressure in element 28. Axle ll may be provided with a 111- brication bore or passage 42 which terminates ad- 3 jacent bearings 38 and may be supplied with lubrication in any suitable manner.

In Figure 4 I show a modified form of my invention. In this figure I show a casing 35 mounted at one end of a rotatable axle 45, such as the driving axle of a motor vehicle, the casing containing a fixed pressure responsive element 41 connected as by conduit 68 to a gauge similar to gauge 33 on the dash of the vehicle, the casing containing a rotatable pressure responsive element in a shell 50 connected as by conduit 49 to the tire of a wheel, the shell having a plurality of pins 5| for engagement with the wheel. Axle i8 is provided with a lubrication passage 52 having an external fitting 53 and adapted to lubricate the thrust plates between the pressure responsive elements the same as the structure of Figures 1 to 3.

The operation of the invention should be apparent from the foregoing description. Pressure responsive element 24, being pressurally connected by tube or conduit 25 totire 12, will expand or contract in an axial direction upon increase or decrease of pressure in the tire. Upon an increase of such pressure, plate 3'5 will be shifted to the right, as seen in Figure 2, thereby shifting plate 34 to the right and causing an increase of pressure in pressure responsive element '28. The pressure in this latter element will be transmitted through conduits 30 and 3?. through shaft bore 3| to the gauge 33. In similar manner a reduction in tire pressure will cause a reverse movement of plates 34 and 3? and the pressure in the tire can be constantly observed on the gauge.

Similar operation occurs with the modification shown in Figure 4, the pressure in element 41 being conducted directly through conduit '48 to the gauge rather than being conducted through the axle shaft.

Although I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and systems.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A tire pressure indicator for a tire on a wheel comprising a casing mounted on the wheel axle independently of the wheel, a fixed pressure responsive element in said casing adapted to actuate a pressure indicator gauge, an inflatable rotary element in said casing expansible axially upon an increase of pressure therein and pressurally connected to said tire, and thrust bearing means between said elements including a pair of plates and bearing elements therebetween, one of said plates having a peripheral retaining flange engagement with the other of said plates, said plates being rotatable with respect to each other and relatively immovable in all other respects.

2. A tire pressure indicator for a tire on a wheel comprising a casing mounted on the Wheel axle independently of the Wheel, a fixed pressure responsive element in said casing adapted to actuate a pressure indicator gauge, an inflatable rotary element in said casing expansible axially upon an increase of pressure therein and pressurally connected to said tire, and thrust bearing means between said elements including a pair of plates and bearing elements therebetween, one of said plates having a peripheral retaining flange and bearing engagement with the other of said plates, said engagement including an inwardly extending radial flange on said first plate, said plates being rotatable with respect to each other and relatively immovable in all other respects.

3. A tire pressure indicator for a tire on a wheel comprising a casing mounted on the wheel axle outside of the wheel having a passage, a fixed pressure responsive element in said casing pressurally connected to said passage and adapted to actuate a pressure indicator gauge, an inflatable rotary element in said casing connected to said wheel and expa'nsible axially upon an increase of pressure therein and pressurally connected to said tire, and thrust bearing means between said elements including a pair of plates having a retaining fiange engagement and bearing elements therebetween, said plates being rotatable with respect to each other andrelatively immovable in all other respects.

RAY L. STEVEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,849,139 Denmire Mar. 15, 1932 2,119,287 Pratt I- May 31, 1938 2,152,159 Smith et al Mar. 28, 1939 2,253,118 Gillespie et al Aug. 19. 1941 

